The Video Electronics Standards Association (VESA) has released the DisplayPort Alternate Mode (Alt Mode) 2.0 standard. DisplayPort is a digital display interface developed by various manufacturers and standardized by VESA that allows internal and external display connections for Ethernet, USB and PCI Express. In June 2019 VESA released DisplayPort 2.0, the first major update to the standard since 2016, which provided a three fold increase in data bandwidth compared to the prior version as well as higher resolution, multiple display configurations and virtual reality displays. DisplayPort Alt Mode 2.0 enhances the previous iteration of the standard, and with the specifications recently released by VESA, will give the upcoming USB4 and USB-C (formerly known as USB Type-C) technologies access to the upgrades.
“VESA’s updated DisplayPort Alt Mode spec includes a number of under-the-hood developments—including updates to interface discovery and configuration as well as power management—to ensure seamless integration with the USB4 specification,” stated Craig Wiley, DisplayPort Alt Mode subgroup leader. “Through our latest collaboration with the USB-IF [USB Implementers Forum], VESA is now taking care of everything related to high-performance displays over USB-C, whether through a native DisplayPort or USB-C connector, or through tunneling of DisplayPort over the native USB4 interface. DisplayPort is also tunneled through the Thunderbolt interface, making it the de facto video standard across PC and mobile displays.”
The DisplayPort Alt Mode 2.0 “provides seamless interoperability” with the new USB4 standard, enabling all of the features of the DisplayPort 2.0 standard version through the USB-3 connector. Using the DisplayPort Alt Mode 2.0, a USB-C connection is able to transmit 80 gigabits per second of video data with the cable’s four high-speed lanes or 40 gigabits with simultaneous SuperSpeed USB data delivery.
“USB Type-C is becoming the connector of choice in notebooks and mobile solutions. With the new DisplayPort Alt Mode 2.0 specification, USB Type-C now delivers compelling single-connector solutions for docking, gaming, AR/VR HMDs, and professional HDR displays that combine 80Gbps of video bandwidth and other important features of DisplayPort 2.0 with the transport of USB data and power delivery,” said Syed Athar Hussain, VESA board vice chairman.
According to Jason Ziller, general manager of the Client Connectivity Division at Intel, the company contributed the Thunderbolt PHY layer specification for use in DisplayPort 2.0, providing rates up to 20 giga transfers per second. “This contribution ensures great user experiences by enabling today’s most versatile port with the highest-performing display capabilities,” said Ziller. Intel collaborated with Apple to develop the Thunderbolt interface.
Products using DisplayPort Alt Mode 2.0 are expected to be available by 2021. USB4 devices could be on the market by late 2020.